• Lemminary@lemmy.world
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    7 months ago

    The non-programmer folks upvote this post. I mean, not that I use it for every app, but I have used it in recent memory. SOH-CAH-TOA, removed!

      • refalo@programming.dev
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        7 months ago

        Programmer for 25 years. Only time I have ever used math more complicated than simple multiply/divide was… actually never.

        That one time when I copy/pasted a formula for linear interpolation, was still just multiplication and division. And I still have no idea how it works.

        I’ve even done OpenGL and graphics programming and still haven’t needed any algebra/trig/etc, although I don’t do complex 3D rendering or physics or anything like that.

        I wish I knew how to do cool programming stuff like draw circles and waves and stuff though, but I’ve never seen a tutorial that didn’t go WAY over my head immediately.

        • FooBarrington@lemmy.world
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          7 months ago

          Drawing a circle is actually pretty simple! Say we want to draw one with:

          • radius r=5
          • center C=(0,0)
          • 1000 points

          The logic would be:

          for (let i = 0; i < 1000; i++) {
              // full circle is made up of 2 * PI angles -> calculate current loop angle
              const angle = (2 * Math.PI) * (i / 1000)
              const x = r * Math.cos(angle)
              const y = r * Math.sin(angle)
              drawPixel(x, y)
          }
          

          The circle starts being drawn at (5, 0). As y approaches -5, x gets smaller until it hits 0. Then x approaches -5 and y approaches 0, and so on.